Many methods have been proposed at present for the purpose of locating the position of the wheels of a vehicle, including methods of location by synchronization and angular correlation, such as in particular the method described in the patent application WO 2012/139711, whose concept is based on the correlation existing between the signals put out by a speed sensor equipping a wheel and synchronized signals put out by a speed sensor mounted on the vehicle in proximity to this wheel.
Such methods of location by synchronization and angular correlation pertain to vehicles having:
r wheels equipped with an electronic unit integrating means of measuring the angular position of said electronic unit and a transmitter designed to transmit signals containing data representative of operating parameters of each wheel and an identification code of said electronic unit,
positioned on the vehicle in proximity to each of the wheels, a wheel speed sensor able to furnish data representative of the orientation of the wheel,
and, integrated in the vehicle, a central unit, on the one hand, provided with a receiver for the receiving of the signals coming from the electronic units, and on the other hand connected to the different wheel speed sensors, and involving, according to the method described in the patent application WO 2012/139711, for the purpose of locating the position of a wheel:
for the electronic unit equipping said wheel, the furnishing to the central unit, at successive times t1 tn, of n signals RF1 . . . RFn transmitted for at least one angular position θ1 . . . θn of said electronic unit, each of the n signals RF1 . . . RFn containing the identification code of the electronic unit and data representative of the angular position θ1 . . . θn of transmission,
for the central unit:                the gathering of the values β1 . . . βn measured by each of the r wheel speed sensors, for each of the successive times t1 to tn, and the determining of so-called compensated values δ1 to δn, determined in relation to a fixed unique reference position, by a compensation of each measured value β1 . . . βn as a function of the data representative of the angular position θ1 . . . θn of transmission of the associated signal RF1 . . . RFn,        the calculating, for each series of compensated values δ1 to δn associated with a wheel speed sensor, of a characteristic value Vn1, Vn2 . . . Vnr representative of the dispersion of said series of values, and the assigning of the identification code of the electronic unit to the position of the wheel situated in proximity to the wheel speed sensor at the origin of the most clustered series of angular values δ1-δn.        
It should be noted that, in the present patent application, we understand the term “angular position θ1 . . . θn of transmission of the RF signals by the electronic units” to mean:
either transmissions for different angular positions θ1 . . . θn of predetermined values,
or transmissions for identical angular positions θ1 . . . θn, and thus transmissions for a fixed angular position,
or transmissions effectuated after predetermined variable periods of time, calculated with a fixed angular position for the origin,
or transmissions combining different angular positions θ1 . . . θn and predetermined variable periods of time with said angular positions θ1 . . . θn for the origins.
The majority of current vehicles being equipped with active safety systems such as “ABS” for antilocking of wheels, and “ESP” for dynamic stability control, such methods of location by synchronization and angular correlation are of major interest especially in terms of installation cost, because the locating of the wheels is done by correlation of the signals furnished by the speed sensors of said active safety system and signals furnished by the speed sensors usually integrated in the electronic units of the monitoring system.
Hence, in fact, the implementing of these methods of location by synchronization and angular correlation simply requires the implementation of software for processing of the signals furnished, but does not need the addition of any specific hardware.
On the other hand, the reliability of such methods of location is based on the ability of the electronic units to furnish the signals RF1 . . . RFn for particular angular positions θ1 . . . θn with restricted margins of error.
Yet it occurs rather frequently in practice that, during the transmission of signals RF1 . . . RFn, the actual angular positions of the electronic units differ from a consistent value as compared to the data representative of the angular position θ1 . . . θn of transmission as transmitted by these signals RF1 . . . RFn, so that this data turns out to consist of aberrant data.
In the majority of cases, such aberrant data only has the consequence of increasing the length of the wheel locating procedure. However, the transmission of this aberrant data may also have the consequence of an errored locating of the position of the wheels.
The only solutions contemplated at present for mitigating the drawbacks involving the transmission of such errored data are solutions based on classical statistical tools.
However, such statistical tools require working with a substantial population in order to evaluate individually the quality of the angular position of each of the transmissions, and therefore these statistical tools require sizeable capacities in terms of data storage memory.
Moreover, the individual evaluation of the quality of the angular position is usually based on a determination of deviations from a mean, and these statistical methods thus need to wait until the population reaches a substantial size in order to obtain relevant decisions. Hence, such statistical methods generate an initial latency period during which the aberrant data cannot be detected or processed.
The present invention intends to mitigate these drawbacks and its first objective is to provide a method of location by synchronization and angular correlation incorporating a procedure for detection of aberrant data regarding the angular position θ1 . . . θn of transmission of the signals by the electronic units, responsive to the first transmissions of signals.
Another objective of the invention is to provide a method of location whose procedure for detection of aberrant data requires slight data storage capacity.
Another objective of the invention is to provide a method of location whose procedure for detection of aberrant data implements a method requiring only available data necessary to the locating of the wheels.